Microcomputers are being applied in the Clinical Pathology Department to extend the capabilities of the Clinical Pathology Laboratory Computer (CPLC) and to automate data acquisition and entry for procedures not previously automated. Two projects have been successfully implemented in this way. The first involved the linking of two Coulter Model S-Plus automated cell counters with the CPLC. Coulter results now can be certified and released by the technologist within minutes of completion of the analysis. The second project resulted in the development of a Computer-Assisted Hematology Morphology Data Handling System. Each of these projects was characterized by the extensive involvement of the technologists in the human factors design considerations. This collaboration ultimately led to the immediate and enthusiastic acceptance of the systems.